Question
I need explaination for number 3 and number 5
from the google, it shows me the answer for number 5 is that All are unique to eukaryotic replication, However, I learned from class differently. what is right?
and this is class lecture slide
DNA Replication 1. Who performed denaturation mapping of phage DNA to demonstrate bidirectional replication? b a) Meselson and Stahl c) John Cairn Schnös and Inman d) Tuneko Okazaki 2. What enzyme in prokaryotes lays down the RNA primers on the lagging strand? a) DNA primase c) DNA polymerase b) DNA helicase d) DNA polymerase II 3. Polymerases that "back up" to remove bases that were incorporated incorrectly are utilizing what activity? )3' to 5' exonuclease activity c) 5 to 3' exonuclease activity b) 3 to 5 polymerase activity d) 5' to 3' polymerase activity 4. Which enzyme extends the DNA at chromosomal ends? a) DNA polymerase l b) DNA polymerase III d Telomerase c) Centromerase 5. Which of the following is NOT a unique aspect of eukaryotic chromosome replication (as compared to prokaryotic replication)? a) Replication is restricted to S phase. b) There is one replicon per chromosome. c) There are many polymerases functioning at the replication fork. d) All are unique to eukaryotic replication. 6. All DNA polymerases synthesize the new strand in what direction? a) polymerases read 3' to 5' and synthesize a 5' to 3' strand b) polymerases read 5' to 3' and synthesize a 3' to 5' strand c) Both A and B are correct (polymerases can synthesize in both directions) d) It depends on if the polymerase has "proof-reading" activity 7. The short synthesized fragments produced on the lagging strand during DNA replication were named after whom? a) Meselson and Stahl c) Schnos and Inmarn b) John Cairn d) Reiji and Tuneko Okazaki 8. What proteins unwind DNA (open it up) at the replication fork? a) DNA topoisomerases b) DNA helicases c) DNA primases d) DNA ligases 9. DNA primase IS NOT needed for replication to occur on the leading DNA strand. a) True b) False
Explanation / Answer
1. b. Schnos and Inman
2. a. DNA primase
3. a. 3' to 5' exonuclease activity
The 3' to 5' exonuclease activity allows the inorrect base to be removed if it has been added by mistake during DNA replication.
4. d. telomerase
5. b. there is one replicon per chromosome
Eukaryotes have multiple replicons per chromosome. Therefore this is the correct option.
6. a. polymerases read in the 3' to 5' direction but synthesize in the 5' to 3' direction
7. d. Reiji and Tuneko Okazaki
8. b. DNA helicases
9. b. False
